Earlier this week, a coalition of legislators introduced the Pregnant Workers Fairness Act, designed to encourage employers to make nice to their pregnant employees. If they need extra bathroom breaks or help lifting heavy things or a chair to sit in, employers shouldn’t balk.

But many are. Complaints about pregnancy-related work discrimination have soared 50% since 2000. Consider the case of Angie, a train conductor in Mississippi whose employer wouldn’t agree to accommodate her when she presented a doctor’s note limiting the amount of weight she should lift. Employees at her workplace routinely helped each other out, but her employer forced her to take three months of unpaid leave rather than assign her to lighter duty. She contacted an advice hotline maintained by Equal Rights Advocates (ERA), a nonprofit law firm that focuses on employment and educational equity for women, but there wasn’t much ERA could do in the absence of comprehensive laws championing pregnant women’s rights to reasonable accommodations in order to keep working.

Just seven states — Connecticut, Hawaii, Louisiana, Alaska, Texas, Illinois and California — have some sort of pregnancy accommodation legislation; New York is in the process of trying to pass a law. California’s is among the most protective for pregnant women: it guarantees the right to job-protected — albeit unpaid — leave and mandates a pregnant woman’s right to be transferred to another position if medically necessary.

Given California’s generosity toward pregnant working women, one might wonder if litigation has gone gangbusters there in the 12 years since its law took effect. And that’s precisely the subject of a new report, Expecting a Baby, Not a Lay-Off: Why Federal Law Should Require the Reasonable Accommodation of Pregnant Workers, released Friday by ERA. It tracks all pregnancy discrimination cases filed in California since 2000 and finds that there just 23 — about two a year. The number of federal law discrimination charges have increased by 54% since 1997, but the charges filed in California dropped, perhaps because the law’s existence compelled employers to negotiate.

“At a time when American families are struggling to make ends meet, it’s imperative that we do everything we can to keep people in their jobs, and this is especially true for pregnant women on the verge of having another mouth to feed,” said U.S. Representative Jerrold Nadler (D-NY), one of the legislators who introduced the Pregnant Workers Fairness Act, in a statement.

Related legislation is particularly important to low-income workers, who tend to be those most impacted. Most women who file pregnancy discrimination claims work at lower-paying jobs in demanding physical environments. “We see that male firefighters who throw out their backs are given desk jobs, but women who are pregnant don’t get them,” says Noreen Farrell, ERA’s executive director. “There is an ability to provide accommodations, but employers don’t want to.”

The legislation is important because other protections out there — namely the Americans with Disabilities Act and the Pregnancy Discrimination Act (PDA), part of the Civil Rights Act — are limited in their application. The PDA, for example, requires employers to treat pregnant workers similarly to the way they treat other workers who may be sick or disabled. But it’s an apples-to-oranges comparison as most pregnant workers are neither sick nor disabled. “There is a gap in how these laws have been applied,” says Farrell. “Some employers say they will provide light duty for people who are injured on the job but not for pregnant women because they are not injured.”

To further complicate matters, some workers are afraid to ask for accommodations for fear they’ll be placed on leave. “They don’t want to start taking leave months before they give birth,” says Farrell. The Family and Medical Leave Act of 1993 provides workers with just 12 weeks of job-protected leave. “They can’t risk starting leave at month three because by month seven, they’ve got no more time left. Even if their employer agrees to keep them on, they’re no longer getting paid.”

All of which is why ERA, along with a host of other organizations, is really hoping the Pregnant Workers Fairness Act will eventually get the seal of approval. “The law has allowed women to continue working at a time when they need to shore up their financial resources and continue to have company health care,” says Farrell. “It’s a win-win for businesses to be able to hang on to happy, well-trained employees.”